Basal Area

AUS-TSR-CON-BAS General High confidence

Benchmark Value

63 m²/ha
Direction: Higher is desirable ↑
Form: MaximumOnly

Scoring Curve

This curve shows how a field measurement for this indicator would score across all available benchmark forms in this context. The scoring engine uses 5 benchmarks together — the OptimalRange form drives the primary score, while 4 guard(s) constrain the result.

Evidence & Context

An upper detrimental threshold is not supported by evidence for this natural system. The ecosystem is self-regulating through competition and natural disturbance (e.g., cyclones), with the upper value of ~63 m²/ha representing a natural saturation point on the most productive sites, not a state of declining health.

Metric Definition:

Stand basal area is the sum of the cross-sectional area of all living tree stems, measured at 1.3 meters above the ground (DBH), within a given unit of land area.

Benchmark Definition:

The upper natural saturation point for basal area in protected Australian tropical rainforests represents the ecosystem's self-regulating capacity through competition and disturbance.

Justification:

The ecosystem self-regulates basal area through competition and natural disturbance, preventing detrimental accumulation.

Sources (1)

Preview of CSIRO Permanent Rainforest Plots of North Queensland, accessed July 20, 2025,
CSIRO Permanent Rainforest Plots of North Queensland, accessed July 20, 2025, Government

Estimating the relative magnitude of expected increases in soil ..., accessed July 18, 2025

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Supporting Sources (4)

Additional references from the underlying research that informed this benchmark.

Preview of Lowland Rainforest of Subtropical Australia ecological community - conservation advice
Lowland Rainforest of Subtropical Australia ecological community - conservation advice
Contextual Support Government

Lowland Rainforest of Subtropical Australia ecological community - conservation advice

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Preview of Lowland Rainforest of Subtropical Australia ecological community - listing advice
Lowland Rainforest of Subtropical Australia ecological community - listing advice
Contextual Support Journal

Lowland Rainforest of Subtropical Australia ecological community - listing advice

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Preview of Patterns of basal area increment, mortality and recruitment were ..., accessed July 20, 2025,
Patterns of basal area increment, mortality and recruitment were ..., accessed July 20, 2025,
Direct Evidence Journal

Patterns of basal area increment, mortality and recruitment were related to logging intensity in subtropical rainforest in Australia over 35 years | Request PDF - ResearchGate

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Preview of Stand basal area, accessed July 12, 2025,
Stand basal area, accessed July 12, 2025,
Contextual Support

Vegetation and floristics of a lowland tropical rainforest in northeast ...

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Context

  • Region Australia
  • Biome Tropical & Subtropical Rainforests
  • Land Use Conservation / Protected Natural Areas
  • Assessment Pristine Reference
  • Evidence Type ReferenceCondition

Lifecycle

  • Status Active
  • Version 1
  • Effective From 22 Mar 2026

Notes

The upper value represents the natural carrying capacity, not a threshold of declining health.